Structure for mounting steering angle sensor for steering

ABSTRACT

In a structure for mounting a steering angle sensor for a steering wheel for detecting a steering angle of a steering wheel, a fitting recessed portion  6  is provided in a side surface of a column ( 4 ) to which a steering-signal transmitting unit ( 3 ), a turn signal lever ( 1 ), and a wiper control switch lever ( 2 ) are attached, and a steering angle sensor ( 5 ) is inserted and fitted into the fitting recessed portion ( 6 ) from the side surface of the column ( 4 ).

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a structure for mounting asteering angle sensor on a steering wheel for detecting the steeringdirection and the steering angle of a steering wheel, and moreparticularly to a structure for mounting a steering angle sensor for asteering wheel which is improved in the assembling efficiency, thehandling efficiency, and maintenance characteristics.

[0002] As shown in FIGS. 10 and 11, for example, a steering angle sensorfor detecting the rotational angle of a steering wheel is arranged suchthat a steering angle sensor unit 105 is inserted from below and fittedinto a sensor mounting recessed portion 106 formed in a lower portion ofa column 104. A turn signal lever 101, a wiper control switch lever 102and a steering-signal transmitting unit 103 which constitute a leverunit are attached to the column 104.

[0003] The steering angle sensor unit 105 has a circular hole 107 in itscentral portion, and a steering shaft is passed through the circularhole 107 so as to fix the steering angle sensor 105 to the column 104.

[0004] However, since the arrangement provided is such that the steeringangle sensor unit 105 is mounted with the steering shaft passedtherethrough, when a failure has occurred in the sensor unit, thesteering wheel and the column 104 must be removed. In addition, in thecase of an airbag-mounted vehicle, a connector for an airbag must beremoved, so that a risk in operation is apprehended.

SUMMARY OF THE INVENTION

[0005] Accordingly, the object of the invention is to provide astructure for mounting a steering angle for a steering wheel whichexcels in the assembling efficiency, the handling efficiency,maintenance characteristics, and safety in operation.

[0006] In order to accomplish the above object, the present invention ischaracterized by having the following arrangement:

[0007] (1) A structure for mounting a steering angle sensor fordetecting a steering angle of a steering wheel, wherein

[0008] a fitting recessed portion is provided in a side surface of acolumn to which a steering-signal transmitting unit, a turn signallever, and a wiper control switch lever are attached, and the steeringangle sensor is inserted and fitted into the fitting recessed portionfrom the side surface of the column.

[0009] (2) The structure according to claim (1), wherein a rotating disklinked to and integrally rotating with a rotating member of thesteering-signal transmitting unit is provided on the column, and asubject detection portion formed in the rotating disk is inserted in aslit formed in a housing of the steering angle sensor.

[0010] (3) The structure according to claim (1), wherein a rotating disklinked to and integrally rotating with a rotating member of thesteering-signal transmitting unit is provided on a column, and a sensorportion projecting from a housing of the steering angle sensor isdisposed on one of an upper side and a lower side of a subject detectionportion formed in the rotating disk.

[0011] (4) A steering angle sensor mounting structure comprising:

[0012] a steering angle sensor for detecting a steering angle of asteering wheel;

[0013] a column to which a steering-signal transmitting unit isattached, the steering-signal transmitting unit including a rotatingmember rotating about an axis; and

[0014] a fitting recessed portion provided in a surface of the columnthrough which the axis does not pass,

[0015] wherein the steering angle sensor is inserted and fitted into thefitting recessed portion, so that the steering angle sensor detects thesteering angle through the rotating member.

[0016] (5) The steering angle sensor mounting structure according to(4), wherein

[0017] the rotating member is provided with a rotating disk,

[0018] the steering angle sensor is provided with a slit, and

[0019] the rotating disk is inserted into the slit when

[0020] the steering angle sensor is fitted to the column.

[0021] (6) The steering angle sensor mounting structure according to(4), wherein

[0022] the rotating member is provided with a rotating disk,

[0023] the steering angle sensor is provided with a sensor portionprojecting therefrom, and

[0024] the sensor portion is disposed on one of an upper side and alower side of the rotating disk.

[0025] (7) The steering angle sensor mounting structure according to(4), wherein

[0026] a turn signal lever and a wiper control switch lever are attachedto surfaces of the column through which the axis does not pass,respectively.

[0027] In the invention, since the steering angle sensor is insertedinto the fitting recessed portion from the side surface of the column soas to be mounted in the column, even if the steering angle sensor fails,the steering angle sensor can be removed from the column withoutremoving the column and the like from the steering shaft, so thatmaintenance is facilitated. In addition, at the time of incorporatingthe steering angle sensor, it is unnecessary to assemble the steeringangle sensor into the steering shaft, so that the assembling efficiency,the handling efficiency, and safety in operation improve substantially.In addition, maintenance can be provided even if a connector for anairbag is not removed, so that safety in operation can be ensured.

[0028] In addition to the abovementioned effect of the invention, sincethe subject detection portion formed in the rotating disk is inserted inthe slit formed in the housing of the steering angle sensor, the sensorportion is protected by a housing body.

[0029] Further in addition to the abovementioned effect of theinvention, although the sensor portion projects from the housing, sincethis sensor portion is inserted into the column, the sensor portion canbe protected.

BRIEF DESCRIPTION OF THE DRAWINGS

[0030]FIG. 1 is a perspective view illustrating a state before mountinga steering angle sensor in a column;

[0031]FIG. 2 is a perspective view illustrating a state in which thesteering angle sensor has been mounted in the column;

[0032]FIG. 3 is a perspective view of the steering angle sensor;

[0033]FIG. 4 is a perspective view illustrating a state in which aportion subject to detection of a rotating disk has entered a slitformed in a housing of the steering angle sensor;

[0034]FIG. 5 is a perspective view of the steering angle sensorillustrating an example in which a sensor portion has projected from thehousing;

[0035]FIG. 6 is a perspective view illustrating a state in which thesensor portion projecting from the housing is disposed on the lower sideof the subject detection portion of the rotating disk;

[0036]FIG. 7 is an exploded perspective view of a steering angle sensorusing a magnetic gear;

[0037]FIG. 8 is an exploded perspective view of the steering anglesensor using the magnetic gear and illustrates a state in which an upperhousing is removed;

[0038]FIG. 9 is an exploded perspective view of the steering anglesensor using the magnetic gear;

[0039]FIG. 10 is a perspective view illustrating a state before arelated steering angle sensor is assembled from below into the column;and

[0040]FIG. 11 is a perspective view illustrating a state in which therelated steering angle sensor is assembled from below into the column.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0041] Referring now to the drawings, a detailed description will begiven of a specific embodiment of the invention.

[0042] Arrangement for Mounting a Steering Angle Sensor

[0043]FIG. 1 is a perspective view illustrating a state before mountingthe steering angle sensor in the column. FIG. 2 is a perspective viewillustrating a state that the steering angle sensor is mounted in thecolumn. FIG. 3 is a perspective view of the steering angle sensor. FIG.4 is a perspective view illustrating a state that a portion subject todetection (hereafter referred to as a subject detection portion) of arotating disk is putted in a slit formed in a housing of the steeringangle sensor. FIG. 5 is a perspective view of the steering angle sensorillustrating an example in which a sensor portion projects from thehousing. FIG. 6 is a perspective view illustrating a state in which thesensor portion projecting from the housing is disposed on the lower sideof the subject detection portion of the rotating disk.

[0044] As shown in FIGS. 1, the structure for mounting a steering anglesensor in accordance with this embodiment is arranged such that asteering angle sensor 5 is fitted to a column 4 to which a turn signallever 1, a wiper control switch lever 2, and a steering-signaltransmitting unit 3 which are constitute a lever unit are attached.

[0045] As shown in FIGS. 1 and 2, the turn signal lever 1 is attached bybeing fitted in a turn-signal-lever attaching hole formed in a rightside surface of the column 4. The wiper control switch lever 2 isattached by being fitted in a wiper-control-switch-lever attaching holeformed in a left side surface of the column 4. The steering-signaltransmitting unit 3 is disposed on a central portion of the main body ofthe column 4.

[0046] It should be noted that although, in this embodiment, the turnsignal lever 1 is disposed on the right-hand side of the column 4 andthe wiper control switch lever 2 on the left-hand side of the column 4,in the case of a left-hand drive vehicle, the turn signal lever 1 isdisposed on the left-hand side of the column 4 and the wiper controlswitch lever 2 on the right-hand side of the column 4.

[0047] The steering-signal transmitting unit 3 is arranged such thatcables for connecting various switches provided on a steering wheel andequipment provided on the vehicle body side are accommodated spirally inan annular space portion defined between a rotating member and a fixedmember, and as the steering wheel is rotated, the cables are paid outfrom a peripheral surface of the rotating member or wound around theperipheral surface of the rotating member.

[0048] The steering angle sensor 5 is inserted and fitted into a fittingrecessed portion 6, formed in a side surface of the column 4, from alateral direction of the column 4, as shown by an arrow in FIG. 4. Asshown in FIGS. 3 and 4, the steering angle sensor 5 is a so-calledtransverse type in which the sensor portion and a circuit board areaccommodated in a housing body 9 constituted by an upper housing 7 and alower housing 8 which are flat-shaped. A slit 10 as an elongated openingis formed in a front surface of this case body 9 on the side from whichthe case body 9 is inserted into the column 4. A flange-like magneticdisk 12 is adapted to be inserted in the slot 10. The magnetic disk 12is integrally formed with a lower end of an annular linking portion 11linked to the rotation member of the steering-signal transmitting unit 3and rotates with the rotating member.

[0049] A subject detection portion having a magnetic pattern in which,for instance, the subject detection portion alternately magnetized withan north pole and a south pole is formed in a periphery of the magneticdisk 12. This subject detection portion is inserted into the slit 10,and a magnetic sensor, mounted on a circuit board 35 disposed in theslit 10, detects the relative density of magnetic lines generated fromthe magnetized magnetic disk 12. The detected relative density of themagnetic lines is subjected to signal processing to detect the steeringangle of the steering wheel.

[0050] It should be noted that, as shown in FIG. 3, a lead-out hole 15for leading, from the circuit board to outside the case body 9, electricwires 14 having a connector 13 provided at their tips is formed in arear surface of the housing body 9.

[0051] In the above-described construction, since the steering anglesensor 5 is inserted into the fitting recessed portion 6 from the sidesurface of the column 4 so as to be mounted in the column 4, even if thesteering angle sensor 5 fails, the steering angle sensor 5 can beremoved from the column 4 without removing the column 4 and the likefrom the steering shaft, so that maintenance is facilitated. Inaddition, at the time of incorporating the steering angle sensor 5, itis unnecessary to assemble the steering angle sensor 5 into the steeringshaft, so that the assembling efficiency, the handling efficiency, andsafety in operation improve substantially. In addition, maintenance canbe provided even if a connector for an airbag is not removed, so thatsafety in operation can be ensured. Furthermore, since the subjectdetection portion formed in the magnetic disk 12 is inserted in the slit10 formed in the housing body 9 of the steering angle sensor 5, thesensor portion is protected by the housing body 9.

[0052] First Modification of the Steering Angle Sensor

[0053]FIGS. 5 and 6 show another example of the steering angle sensoraccording to the present invention. This steering angle sensor 21 is aso-called vertical type in which the circuit board is accommodated in ahousing body 24 constituted by a vertically elongated lower housing 22and an upper housing 23 functioning as a cover. A sensor portion 25projects horizontally from the front surface of the case body 24 on thisside from which the case body 24 is inserted into the column 4. Thesensor portion 25 is disposed on an upper or lower side of the magneticdisk 12 in such a manner as to oppose the magnetic pattern formed on themagnetic disk 12.

[0054] It should be noted that the lead-out hole 15 for leading from thecircuit board to outside the case body 24 the electric wires 14 havingthe connector 13 provided at their tips is formed in the rear surface ofthe housing body 24.

[0055] According to this steering angle sensor 21, although the sensorportion 25 projects from the housing body 9, since this sensor portion25 is inserted into the column 4, the sensor portion 25 can beprotected.

[0056] Second Modification of the Steering Angle Sensor

[0057]FIGS. 7 and 9 show another example of the steering angle sensor.This steering angle sensor 31 is a sensor of the transverse type shownin FIG. 3. A circuit board 35, a connecting gear 36 a provided rotatablyon the circuit board 35, and a magnetic gear 36 b are accommodated in ahousing body 34 constituted by an upper housing 32 and a lower housing33.

[0058] As shown in FIG. 7, a connector 37, for connecting the ends ofthe electric wires 14 having the connector 13 provided at their tips, isprovided on the circuit board 35. As the magnetic gear 36 b, one inwhich a magnetic material is molded into a gear shape or one in which aplastic magnet is formed into a gear shape, is used. The connecting gear36 a is adapted to be engaged with a rotating gear 39 formed integrallywith a lower end of a linking portion 38 for linking to the rotatingmember of the steering-signal transmitting unit 3, and transmits therotation of the rotating gear 39 to the magnetic gear 36 b.

[0059] In this gear mechanism, a reduction gear is employed fordetecting the rotation of the steering wheel within one rotation of themagnetic gear 36 b, that is, the maximum rotation amount of the steeringwheel is defined by one rotation off the magnetic gear 36 b. Forexample, in an automobile, since the steering wheel undergoes tworevolutions for each of the left and right turns, the steering wheelundergoes four turns in total. Thus, the magnetic gear 36 b isdecelerated so as to undergo one revolution when the steering wheelundergoes four revolutions. At that time, any number of gears may beused in the reduction gear mechanism. Further, an arbitrary reductiongear ratio is not fixed, and may be set arbitrarily.

[0060] The subject detection portion having the magnetic pattern inwhich, for instance, the subject detection portion alternatelymagnetized with an north pole and a south pole is formed in the magneticgear 36 b, and the relative density of magnetic lines generated from themagnetic gear 36 b is detected by the magnetic sensor mounted on thecircuit board 35, and is subjected to signal processing to detect thesteering angle of the steering wheel.

[0061] Although a description has been given above of the embodiment,the invention is not limited to the same, and various modificationswithout departing from the gist of the invention are possible.

[0062] For example, if a slit is formed in the magnetic gear 36 b shownin FIGS. 8 and 9, the steering angle of the steering wheel can bedetected optically.

[0063] As is clear from the foregoing description, in accordance withthe invention, since the steering angle sensor is inserted into thefitting recessed portion from the side surface of the column so as to bemounted in the column, even if the steering angle sensor fails, thesteering angle sensor can be removed from the column without removingthe column and the like from the steering shaft, so that maintenance isfacilitated. In addition, at the time of incorporating the steeringangle sensor, it is unnecessary to assemble the steering angle sensor 5into the steering shaft, so that the assembling efficiency, the handlingefficiency, and safety in operation improve substantially. In addition,maintenance can be provided even if a connector for an airbag is notremoved, so that safety in operation can be ensured.

[0064] Further, in accordance with the invention, since the subjectdetection portion formed in the rotating disk is inserted in the slitformed in the housing of the steering angle sensor, the sensor portioncan be protected by a housing body.

[0065] Further, in accordance with the invention, although the sensorportion projects from the housing, since this sensor portion enters thecolumn, the sensor portion can be protected.

What is claimed is:
 1. A structure for mounting a steering angle sensorfor detecting a steering angle of a steering wheel, wherein a fittingrecessed portion is provided in a side surface of a column to which asteering-signal transmitting unit, a turn signal lever, and a wipercontrol switch lever are attached, and the steering angle sensor isinserted and fitted into the fitting recessed portion from the sidesurface of the column.
 2. The structure according to claim 1, wherein arotating disk linked to and integrally rotating with a rotating memberof the steering-signal transmitting unit is provided on the column, anda subject detection portion formed in the rotating disk is inserted in aslit formed in a housing of the steering angle sensor.
 3. The structureaccording to claim 1, wherein a rotating disk linked to and integrallyrotating with a rotating member of the steering-signal transmitting unitis provided on a column, and a sensor portion projecting from a housingof the steering angle sensor is disposed on one of an upper side and alower side of a subject detection portion formed in the rotating disk.4. A steering angle sensor mounting structure comprising: a steeringangle sensor for detecting a steering angle of a steering wheel; acolumn to which a steering-signal transmitting unit is attached, thesteering-signal transmitting unit including a rotating member rotatingabout an axis; and a fitting recessed portion provided in a surface ofthe column through which the axis does not pass, wherein the steeringangle sensor is inserted and fitted into the fitting recessed portion,so that the steering angle sensor detects the steering angle through therotating member.
 5. The steering angle sensor mounting structureaccording to claim 4, wherein the rotating member is provided with arotating disk, the steering angle sensor is provided with a slit, andthe rotating disk is inserted into the slit when the steering anglesensor is fitted to the column.
 6. The steering angle sensor mountingstructure according to claim 4, wherein the rotating member is providedwith a rotating disk, the steering angle sensor is provided with asensor portion projecting therefrom, and the sensor portion is disposedon one of an upper side and a lower side of the rotating disk.
 7. Thesteering angle sensor mounting structure according to claim 4, wherein aturn signal lever and a wiper control switch lever are attached tosurfaces of the column through which the axis does not pass,respectively.